Electric conductor.



No. 723,717. PATENTED MAR. 24, 1903.

J. D. NICHOLSON.

ELECTRIC CONDUCTOR.

APPLICATION FILED AUG.17. 1900. no MonnL.

WITNESSES: 48 izkaah INVENTOR 444/47 BY ATTO R N EY UNITED STATES 'ATENTFFICE.

JOHN D. NICHOLSON, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR TO THEPITTSBURGH REDUCTION COMPANY, OF- PITTSBURG, PENNSYLVANIA, A CORPORATIONOF PENNSYLVANIA. I

ELECTRIC CONDUCTOR.

SPECIFICATION forming part of Letters Patent N 0. 723,717, dated March24, 1903.

Application filed August 11,1900. Serial to. 27,196. (Noniodeli) To allwhom it may concern: Be it known that I, JOHN D. NICHOLSON, a citizen ofthe United States, and a resident of Pittsburg, in the county ofAllegheny and State of Pennsylvania, have invented a certain new anduseful Improvement in Electrical Conductors, of which the following is aspecification.

r This invention relates to a novel electrical re, conductor or wire;and it consists in a wire drawn or rolled from a compound ingotmade oftwo metals, one being copper and the other aluminium, substantially ashereinafter fully described and claimed.

r 5 In the drawing which forms partof this specification the figure is atransverse section of my compound wire.

Some of the more pertinent physical characteristics of aluminium andcopper are as :0 follows:

The two metals readily-fuse together to form alloys of more orless valuein the mechanical arts; but the important electric characteristics thenno longer exist. The electric conductivity, for example, diminishesrapidly with the addition of copper, while the tensile strength mayincrease greatly.

I have found that a wire can be readily drawn from a compound ingotcomposed of Q the two metals poured or formed'se'parately,

' 'in some cases the core being of copper and the shell of aluminium, inother cases thereverse.

'45 In such a wire each metal preserves its own characteristics and bothmetals partake in the increase of tensile strength due to the operationof drawing. The conductivity of either remains intact. Bydulyproportioning the two metals the resultant strength, conductiv- 5'0 ity,sectional area, or weight may be brought to any desired standard.

I prefer to make the compound wire with a. copper core and aluminiumshell on account of the greatly-reduced liability to corrosion. Incoupling such wires or making branch connections the difiicultyordinarily found in soldering aluminium is not serious, as the copperpart of the conductor can be readily soldered without seriously raisingthe resistance 6:: of the joint.

The particular method of forming the com pound ingot may vary, as thatis not of the essence of my present invention. A simple way is bycasting first acore of copper, it having the higher melting-point,andthen while this is at or near the melting-point of alue minium castingthe shell of the latter around such copper core, or the operation maybereversed as to positions, the first cast, of copper, being the shell andthe cast of aluminium being the core, or in some cases the hollow andsolid ingots may be separately formed and consolidated by hydraulic orother pressure applied before or after cooling or while the core is coldand the shell still heated.

In referring to either of the two component parts of my new conductor Iwish to say that they are supposed to be substantially pure; but thepresence of slight admixtures of phos- 8c phorusor other well-knowndeoxidizing reagents is not objectionable, provided the individualcharacteristics of the two metals are substantially preserved. I

I claim as my invention- A compound electrical conductor composed of acore and a-shell of different metals drawn into wire, one metal beingaluminium and the other copper.

Signed at the city of Belfast, Ireland, this 0 9th day of July, 1900. V

- JOHN D. NICHOLSON;

Witnesses:

JOHN M. QUADE, BERNARD PEAKE.

